Condensing unit/A-coil help

I am looking to add central air to the house we just purchased this past fall.
The house is 1287 on the main, 583 lower and 217 upper level for square footage.

I need to figure out how large of an A-coil to buy, and what tonnage I would need.
I picked up a York Model H1RA048S25G condensing unit. But nowhere on the unit does it say what ton it is rated at.

It has the model # listed above.
7lbs 5oz R22 charge
High side pressure 350
Low side pressure 300
and the serial number.

I have called the local and they were no help at all.

Any help would be appreciated.
Thanks
Willis